textproduct: Rapid City

KEY MESSAGES

-Warming up this weekend with gusty southeast winds Saturday

-Strong low pressure will cross the region Sunday-Monday, bringing potentially severe weather Sunday, with good chance of rain most places

-Drier and seasonal next week after Monday

DISCUSSION

(This Evening Through Friday) Issued at 208 PM MDT Fri Apr 25 2025

Deep upper trough will push into the Rockies this weekend and set the stage for a potent low pressure system early next week, with a pattern shift to mean western CONUS toughing after. Easterly flow has become established across the region as the sfc high shifts east. Expect that low clouds and areas of drizzle will develop again tonight, esp along the eastern slopes of the Black Hills as moist easterly upslope flow continues Otherwise, a weak embedded impulse will move through the region tonight into Sat and may support a few isolated showers with pos theta-e adv ensuing. Deep upper trough will then dig into the western CONUS Sat. Pressure falls will increase across the region Sat, supporting gusty SE winds, with potential adv level winds over NW SD. This system will shift east Sunday with the warm sector spreading over the region. This will support very warm temps with highs in the 70s and 80s, warmest on the SD Plains. Prefrontal trough will support thunderstorm chances in the late afternoon/evening with some potential for severe weather as sufficient CAPE and bulk layer shear will be in place. TS development is highly conditional and will hinge on the scope and depth of moisture return. There is plenty of gulf moisture that will wrap into this system, which will tend to favor a good setup for appreciable rains and thunderstorms. Wrap around rains (high elevation snow) will then move into the region from the NW Sunday night as the cold front shifts east. Rain will continue Monday in the northwest half, with convection possible in the vigorous deformation zone. Things dry out some the remainder of next week with additional chances for showers later in the week as more impulses traverse the flow, with seasonal temps expected. Given expected western CONUS troughing toward the end of next week, a period of very warm temps will be possible by next weekend.

AVIATION

(For the 00Z TAFS Through 00Z Saturday Evening) Issued At 540 PM MDT Fri Apr 25 2025

Predominately MVFR conditions with intermittent IFR conditions will persist across the KRAP and KGCC terminals through 15z. Expect periods of -DZ through 06z at KRAP terminal. Conditions will improve across the terminals by 19z but strong south winds are progged to impact the terminal beginning around 15z where winds could gust up to 40 knots.

UNR WATCHES/WARNINGS/ADVISORIES

SD...None. WY...None.